Sink



FIG. 1 is a front perspective view of a sink showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a rear view thereof;

FIG. 4 is a side view thereof;

FIG. 5 is a side view of the opposite side of FIG. 4;

FIG. 6 is a top view thereof; and,

FIG. 7 is a bottom view thereof.

CLAIM I claim the ornamental design for a sink, as shown and described.